Oat growers and processors need a meticulous management system to guarantee less than 20 parts per million of gluten
MOOSE JAW, Sask. — The gluten-free oat market is an opportunity for growers who can keep their crop clean from start to finish.
Shelley Case, a Regina dietitian and expert on celiac disease and its required gluten-free diet, told the Prairie Oat Growers Association annual meeting that it doesn’t take much contamination from wheat, barley, rye or triticale to push gluten levels too high.
Canadian regulations adopted in May define gluten-free as a food containing no more than 20 parts per million of gluten.
“So, in 100 grams of food, you cannot have more than two milligrams,” Case said.
“That’s your absolute cutoff.”
Just three barley kernels would contaminate a one kilogram container of oats that contained up to 35,000 seeds, she said.
Case emphasized that is a maximum that can’t be exceeded anywhere along the chain.
Studies in Europe and North America have found contamination at various levels, even in products that would naturally be gluten-free.
A Canadian study from 2013 found that three of 268 packages of products labeled gluten-free contained more than 20 parts per million.
The same study found that 30 of 298 products with no gluten-free statement were above the threshold.
As well, 29 of 74 products that had precautionary warnings such as “may contain” did contain more than 20 p.p.m.
Case said some of these results would explain why people become ill after eating products that should be safe, including oats. Some people have claimed they have become ill even after eating oats that were certified gluten-free.
It’s hard to know if the problem was contamination or something else, such as the fibre content of oats.
A small group of people are intolerant to oats that are guaranteed to be safe, and the reason isn’t yet clear. Gluten-containing grain routinely contaminates regular oats, and consumers have to know which are appropriate for them, she added.
The demand for certified gluten-free oats is strong. Case said oats offers nutrients that typical gluten-free bases such as rice flour and other starches don’t have, such as betaglucan, iron, protein, vitamin B and higher fibre.
However, even eating products that contain the maximum of 20 p.p.m. can be a gamble, she added.
For example, someone who ate 500 grams of different gluten-free products a day that each had exactly 20 p.p.m., or two milli-grams, would be eating 10 mg per day.
Sensitivity studies have found people start having problems at 10 mg per day and damage to the small intestine at 50 mg per day after only three months.
Case said that’s important for oat growers and processors to recognize as they market their products. They want to be well below the 20 p.p.m maximum.
“Gluten-free oats is a complete management system,” she said.
“You start clean, you stay clean.”
Seed purity, crop rotation, dedicated or thoroughly cleaned equipment and testing are critical parts of such a system. Crop rotation with pulses, flax and canola isn’t an issue because those crops are naturally gluten-free.
Crops destined for the gluten-free market should be tested with the Ridascreen R-7001 Gliadin ELISA test. Some tests pick out wheat but not barley.
Tests should also be done on representative samples and shouldn’t be composited.
For example, samples with less than 20 p.p.m. shouldn’t be mixed with those much higher with the intent of blending to lower the overall content.
“This is a food safety issue,” Case said.